{"id":107,"date":"2023-09-24T22:29:19","date_gmt":"2023-09-24T14:29:19","guid":{"rendered":"https:\/\/xiuxiejiang.com\/?p=107"},"modified":"2023-09-24T22:29:19","modified_gmt":"2023-09-24T14:29:19","slug":"different-java-and-cs","status":"publish","type":"post","link":"https:\/\/xiuxiejiang.com\/index.php\/2023\/09\/24\/different-java-and-cs\/","title":{"rendered":"Java \u548c C# \u6700\u5927\u7684\u4e0d\u540c\u662f\u4ec0\u4e48\uff1f"},"content":{"rendered":"\n

\u539f\u6587\uff1aJava \u548c C# \u6700\u5927\u7684\u4e0d\u540c\u662f\u4ec0\u4e48\uff1f – \u77e5\u4e4e (zhihu.com)<\/a><\/p>\n\n\n\n

\u6211\u89c9\u5f97\u629b\u5f00\u8bed\u6cd5\u800c\u8c08\uff0c\u6700\u4e3b\u8981\u7684\u8fd8\u662f\u5bf9\u5e95\u5c42\u7684\u63a7\u5236\u80fd\u529b\u4e0d\u540c\u3002<\/p>\n\n\n\n

C# \u4e00\u5f00\u59cb\u867d\u7136\u501f\u9274 Java\uff0c\u4f46\u662f\u76ee\u7684\u5b8c\u5168\u4e0d\u662f\u4e3a\u4e86\u9020\u4e00\u4e2a better Java\uff0c\u800c\u662f\u9020\u4e00\u4e2a better C++\u3002\u6e38\u620f\u5f15\u64ce\u4eec\u504f\u7231 C# \u4e5f\u662f\u6709\u8fd9\u4e00\u5c42\u539f\u56e0\u5728\u91cc\u9762\uff0c\u8fd9\u4e00\u70b9\u9ad8\u8d5e\u56de\u7b54\u4e2d\u00a0<\/p>\n\n\n\n

@MaxwellGeng\u00a0\u7684\u56de\u7b54\u5df2\u7ecf\u8db3\u591f\u80fd\u8bf4\u6e05\u4e86\u3002<\/p>\n\n\n\n

\u6bd4\u5982\u5728 C# \u91cc\u9762\u4f60\u80fd\u5e72\u7684\uff1a<\/p>\n\n\n\n

var x = new int[10];\nfixed (int* p = x)\n{\n    Console.WriteLine(*((long*)p - 1)); \/\/ 10\n}\n<\/pre>\n\n\n\n
\u4e0a\u8ff0\u4ee3\u7801\u4f1a\u8f93\u51fa 10\uff0c\u4e3a\u4ec0\u4e48\uff1f\u56e0\u4e3a .NET \u4e2d\u6570\u7ec4\u7684\u957f\u5ea6\u5b58\u50a8\u4e8e\u6570\u7ec4\u7b2c\u4e00\u4e2a\u5143\u7d20\u4e4b\u524d\u7684 8 \u5b57\u8282\u5185\u5b58\u4e2d\u3002\u5982\u679c\u4f60\u518d\u63a5\u7740\u8f93\u51fa *((long*)p - 2)<\/code>\uff0c\u5c06\u4f1a\u76f4\u63a5\u5f97\u5230\u8fd9\u4e2a\u5bf9\u8c61\u7684 TypeHandle<\/code> \u5730\u5740\uff1a<\/p>\n\n\n\n
Console.WriteLine((long)typeof(int[]).TypeHandle.Value == *((long*)p - 2)); \/\/ True\n<\/pre>\n\n\n\n
\u7136\u540e\u62ff\u7740\u8fd9\u4e2a\u6307\u9488\u53c8\u63a5\u7740\u80fd\u53bb\u8bbf\u95ee\u5bf9\u8c61\u7684 MethodTable<\/code>\u3002<\/p>\n\n\n\n
\u518d\u6709\u4f60\u8fd8\u53ef\u4ee5\u624b\u52a8\u5728\u6808\u4e0a\u5206\u914d\u7a7a\u95f4\uff1a<\/p>\n\n\n\n
var x = stackalloc int[2]; \/\/ \u6216\u8005 Span<int> x = stackalloc int[2]; \u505a\u5b89\u5168\u8bbf\u5b58\nx[0] = 3;\nx[1] = 1;\nConsole.WriteLine(x[0] + x[1]); \/\/ 4\n<\/pre>\n\n\n\n
\u63a5\u7740\u4f60\u60f3\u7ed5\u8fc7 GC \u76f4\u63a5\u624b\u52a8\u5206\u914d\u5806\u5185\u5b58\uff1a<\/p>\n\n\n\n
var array = (int*)NativeMemory.Alloc(10, sizeof(int));\narray[0] = 1;\narray[1] = 3;\nConsole.WriteLine(array[0] + array[1]); \/\/ 4\nNativeMemory.Free(array);\n<\/pre>\n\n\n\n
\u4e0a\u8ff0\u8c03\u7528\u7b49\u4ef7\u4e8e\u4f60\u5728 C \u8bed\u8a00\u4e2d\u8c03\u7528\u7684\u00a0malloc<\/code>\uff0c\u6b64\u5916\u8fd8\u6709\u00a0AllocAligned<\/code>\u3001Realloc<\/code>\u3001AllocZeroed<\/code>\u00a0\u7b49\u7b49\uff0c\u53ef\u4ee5\u76f4\u63a5\u63a7\u5236\u5185\u5b58\u5bf9\u9f50\u3002<\/p>\n\n\n\n
\u63a5\u4e0b\u6765\u4f60\u60f3\u521b\u5efa\u4e00\u4e2a\u663e\u5f0f\u5185\u5b58\u5e03\u5c40\u7684\u7ed3\u6784 Foo<\/code>\uff1a<\/p>\n\n\n\n
var obj = new Foo();\nobj.Float = 1;\nConsole.WriteLine(obj.Int); \/\/ 1065353216\nConsole.WriteLine(obj.Bytes[0]); \/\/ 0\nConsole.WriteLine(obj.Bytes[1]); \/\/ 0\nConsole.WriteLine(obj.Bytes[2]); \/\/ 128\nConsole.WriteLine(obj.Bytes[3]); \/\/ 63\n\n[StructLayout(LayoutKind.Explicit)]\nstruct Foo\n{\n    [FieldOffset(0)] public int Int;\n    [FieldOffset(0)] public float Float;\n    [FieldOffset(0)] public unsafe fixed byte Bytes[4];\n}\n<\/pre>\n\n\n\n
\u7136\u540e\u4f60\u5c31\u6210\u529f\u6a21\u62df\u51fa\u4e86\u4e00\u4e2a C \u7684 Union\uff0c\u4e4b\u6240\u4ee5\u4f1a\u6709\u4e0a\u9762\u7684\u8f93\u51fa\uff0c\u662f\u56e0\u4e3a\u5355\u7cbe\u5ea6\u6d6e\u70b9\u6570\u00a01 \u7684\u4e8c\u8fdb\u5236\u8868\u793a\u4e3a\u00a00x00111111100000000000000000000000<\/code>\uff0c\u4ee5\u5c0f\u7aef\u65b9\u5f0f\u5b58\u50a8\u540e\u5360 4 \u4e2a\u5b57\u8282\uff0c\u5206\u522b\u662f\u00a00x00000000<\/code>\u30010x00000000<\/code>\u30010x10000000<\/code>\u30010x00111111<\/code>\u3002<\/p>\n\n\n\n
\u8fdb\u4e00\u6b65\uff0c\u4f60\u8fd8\u80fd\u76f4\u63a5\u4ece\u5185\u5b58\u6570\u636e\u6ca1\u6709\u4efb\u4f55\u62f7\u8d1d\u5f00\u9500\u5730\u6784\u9020\u5bf9\u8c61\uff1a<\/p>\n\n\n\n
var data = stackalloc byte[] { 0, 0, 128, 63 };\nvar foo = Unsafe.AsRef<Foo>(data);\nConsole.WriteLine(foo.Float); \/\/ 1\n\n[StructLayout(LayoutKind.Explicit)]\nstruct Foo\n{\n    [FieldOffset(0)] public int Int;\n    [FieldOffset(0)] public float Float;\n    [FieldOffset(0)] public unsafe fixed byte Bytes[4];\n}\n<\/pre>\n\n\n\n
\u751a\u81f3\u8fd9\u6837\uff1a<\/p>\n\n\n\n
var data = 1065353216;\nvar foo = Unsafe.AsRef<Foo>(&data);\nConsole.WriteLine(foo.Float); \/\/ 1\n\n[StructLayout(LayoutKind.Explicit)]\nstruct Foo\n{\n    [FieldOffset(0)] public int Int;\n    [FieldOffset(0)] public float Float;\n    [FieldOffset(0)] public unsafe fixed byte Bytes[4];\n}\n<\/pre>\n\n\n\n
\u4ece\u5806\u5185\u5b58\u521b\u5efa\u81ea\u7136\u4e5f\u6ca1\u95ee\u9898\uff1a<\/p>\n\n\n\n
var data = new byte[] { 0, 0, 128, 63 };\nfixed (void* p = data)\n{\n    var foo = Unsafe.AsRef<Foo>(p);\n    Console.WriteLine(foo.Float); \/\/ 1\n}\n\n[StructLayout(LayoutKind.Explicit)]\nstruct Foo\n{\n    [FieldOffset(0)] public int Int;\n    [FieldOffset(0)] public float Float;\n    [FieldOffset(0)] public unsafe fixed byte Bytes[4];\n}\n<\/pre>\n\n\n\n
\u518d\u6bd4\u5982\uff0c\u6b64\u65f6\u4f60\u9762\u524d\u6709\u4e00\u4e2a\u4f7f\u7528 C++ \u7f16\u5199\u7684\u5e93\uff0c\u5176\u4e2d\u6709\u8fd9\u4e48\u4e00\u6bb5\u4ee3\u7801\uff1a<\/p>\n\n\n\n
#include <cstring>\n#include <cstdio>\n\nextern \"C\" __declspec(dllexport)\nchar* __cdecl foo(char* (*gen)(int), int count) {\n    return gen(count);\n}\n<\/pre>\n\n\n\n
\u7136\u540e\u6211\u4eec\u7f16\u5199\u5982\u4e0b C# \u4ee3\u7801\uff1a<\/p>\n\n\n\n
[DllImport(\".\/foo.dll\", EntryPoint = \"foo\"), SuppressGCTransition]\nstatic extern string Foo(delegate* unmanaged[Cdecl]<int, nint> gen, int count);\n\n[UnmanagedCallersOnly(CallConvs = new[] { typeof(CallConvCdecl) }), SuppressGCTransition]\nstatic nint Generate(int count)\n{\n    var str = Enumerable.Repeat(\"w\", count).Aggregate((a, b) => $\"{a}{b}\");\n    return Marshal.StringToHGlobalAnsi(str);\n}\n\nvar f = (delegate* unmanaged[Cdecl]<int, nint>)&Generate;\nvar result = Foo(f, 5);\nConsole.WriteLine(result); \/\/ wwwww\n<\/pre>\n\n\n\n
\u4e0a\u9762\u7684\u4ee3\u7801\u5e72\u4e86\u4ec0\u4e48\u4e8b\u60c5\uff1f\u6211\u4eec\u5c06 C# \u7684\u51fd\u6570\u6307\u9488\u4f20\u5230\u4e86 C++ \u4ee3\u7801\u4e2d\uff0c\u7136\u540e\u5728 C++ \u4fa7\u8c03\u7528 C# \u51fd\u6570\u751f\u6210\u4e86\u4e00\u4e2a\u5b57\u7b26\u4e32 wwwww<\/code>\uff0c\u7136\u540e\u5c06\u8fd9\u4e2a\u5b57\u7b26\u4e32\u8fd4\u56de\u7ed9 C# \u4fa7\u3002\u800c\u5c31\u7b97\u4e0d\u7528\u51fd\u6570\u6307\u9488<\/a>\u6362\u6210\u4f7f\u7528\u59d4\u6258\u4e5f\u6ca1\u6709\u533a\u522b\uff0c\u56e0\u4e3a .NET \u4e2d\u7684\u59d4\u6258\u4e0b\u9762\u5c31\u662f\u51fd\u6570\u6307\u9488\u3002<\/p>\n\n\n\n
\u751a\u81f3\uff0c\u5982\u679c\u6211\u4eec\u4e0d\u60f3\u8ba9 .NET \u5bfc\u5165 foo.dll<\/code>\uff0c\u6211\u4eec\u60f3\u81ea\u884c\u51b3\u5b9a\u52a8\u6001\u5e93<\/a>\u7684\u751f\u547d\u5468\u671f\uff0c\u8fd8\u53ef\u4ee5\u8fd9\u4e48\u5199\uff1a<\/p>\n\n\n\n
[UnmanagedCallersOnly(CallConvs = new[] { typeof(CallConvCdecl) }), SuppressGCTransition]\nstatic nint Generate(int count)\n{\n    var str = Enumerable.Repeat(\"w\", count).Aggregate((a, b) => $\"{a}{b}\");\n    return Marshal.StringToHGlobalAnsi(str);\n}\n\nvar f = (delegate* unmanaged[Cdecl]<int, nint>)&Generate;\nvar library = NativeLibrary.Load(\".\/foo.dll\");\nvar foo = (delegate* unmanaged[Cdecl, SuppressGCTransition]<delegate* unmanaged[Cdecl]<int, nint>, int, string>)NativeLibrary.GetExport(library, \"foo\");\nvar result = foo(f, 5);\nConsole.WriteLine(result); \/\/ wwwww\nNativeLibrary.Free(library);\n<\/pre>\n\n\n\n
\u4e0a\u9762\u8fd9\u4e9b\u90fd\u4e0d\u662f Windows \u4e13\u7528\uff0c\u5728 Linux\u3001macOS \u4e0a\u5bfc\u5165 .so<\/code> \u548c .dylib<\/code> \u90fd\u5b8c\u5168\u4e0d\u5728\u8bdd\u4e0b\u3002<\/p>\n\n\n\n
\u518d\u6709\uff0c\u6211\u4eec\u6709\u4e00\u4e9b\u6570\u636e\u60f3\u8981\u8fdb\u884c\u8ba1\u7b97\uff0c\u4f46\u662f\u6211\u4eec\u60f3\u4f7f\u7528 SIMD \u8fdb\u884c\u5904\u7406\uff0c\u90a3\u53ea\u9700\u8981\u8fd9\u4e48\u5199\uff1a<\/p>\n\n\n\n
var vec1 = Vector128.Create(1.1f, 2.2f, 3.3f, 4.4f);\nvar vec2 = Vector128.Create(5.5f, 6.6f, 7.7f, 8.8f);\n\nConsole.WriteLine(Calc(vec1, vec2));\n\nfloat Calc(Vector128<float> l, Vector128<float> r)\n{\n    if (Avx2.IsSupported)\n    {\n        var result = Avx2.Multiply(l, r);\n        float sum = 0;\n        for (var i = 0; i < Vector128<float>.Count; i++) sum += result.GetElement(i);\n        return sum;\n    }\n    else if (Rdm.IsSupported)\n    {\n        var result = Rdm.Multiply(l, r);\n        float sum = 0;\n        for (var i = 0; i < Vector128<float>.Count; i++) sum += result.GetElement(i);\n        return sum;\n    }\n    else\n    {\n        float sum = 0;\n        for (int i = 0; i < Vector128<float>.Count; i++)\n        {\n            sum += l.GetElement(i) * r.GetElement(i);\n        }\n        return sum;\n    }\n}\n<\/pre>\n\n\n\n
\u53ef\u4ee5\u770b\u770b\u5728 X86 \u5e73\u53f0\u4e0a\u751f\u6210\u4e86\u4ec0\u4e48\u4ee3\u7801\uff1a<\/p>\n\n\n\n
vzeroupper\t\nvmovupd\txmm0, [r8]\nvmulps\txmm0, xmm0, [r8+0x10]\nvmovaps\txmm1, xmm0\nvxorps\txmm2, xmm2, xmm2\nvaddss\txmm1, xmm1, xmm2\nvmovshdup\txmm2, xmm0\nvaddss\txmm1, xmm2, xmm1\nvunpckhps\txmm2, xmm0, xmm0\nvaddss\txmm1, xmm2, xmm1\nvshufps\txmm0, xmm0, xmm0, 0xff\nvaddss\txmm1, xmm0, xmm1\nvmovaps\txmm0, xmm1\nret<\/pre>\n\n\n\n
\u5e73\u53f0\u5224\u65ad\u7684\u5206\u652f\u4f1a\u88ab JIT \u81ea\u52a8\u6d88\u9664\u3002\u4f46\u5176\u5b9e\u9664\u4e86\u624b\u52a8\u7f16\u5199 SIMD \u4ee3\u7801\u4e4b\u5916\uff0c\u524d\u4e24\u4e2a\u5206\u652f\u5b8c\u5168\u53ef\u4ee5\u4e0d\u5199\uff0c\u800c\u53ea\u7559\u4e0b\uff1a<\/p>\n\n\n\n
float Calc(Vector128<float> l, Vector128<float> r)\n{\n    float sum = 0;\n    for (int i = 0; i < Vector128<float>.Count; i++)\n    {\n        sum += l.GetElement(i) * r.GetElement(i);\n    }\n    return sum;\n}\n<\/pre>\n\n\n\n
\u56e0\u4e3a\u73b0\u9636\u6bb5\u5f53\u5faa\u73af\u8fb9\u754c\u6761\u4ef6\u662f\u5411\u91cf\u957f\u5ea6\u65f6\uff0c.NET \u4f1a\u81ea\u52a8\u4e3a\u6211\u4eec\u505a\u5411\u91cf\u5316\u5e76\u5c55\u5f00\u5faa\u73af\u3002<\/p>\n\n\n\n
\u90a3\u4e48\u7ee7\u7eed\uff0c\u6211\u4eec\u8fd8\u6709ref<\/code>\u3001in<\/code>\u3001out<\/code>\u6765\u505a\u5f15\u7528\u4f20\u9012\u3002<\/p>\n\n\n\n
\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u5f88\u5927\u7684 struct<\/code>\uff0c\u6211\u4eec\u4e3a\u4e86\u907f\u514d\u4f20\u9012\u65f6\u53d1\u751f\u62f7\u8d1d\uff0c\u53ef\u4ee5\u76f4\u63a5\u7528 in<\/code> \u6765\u505a\u53ea\u8bfb\u5f15\u7528\u4f20\u9012\uff1a<\/p>\n\n\n\n
void Test(in Foo v) { }\n\nstruct Foo\n{\n    public long A, B, C, D, E, F, G, H, I, J, K, L, M, N;\n}\n<\/pre>\n\n\n\n
\u800c\u5bf9\u4e8e\u5c0f\u7684 struct<\/code>\uff0c.NET \u6709\u4e13\u95e8\u7684\u4f18\u5316\u5e2e\u6211\u4eec\u5f7b\u5e95\u6d88\u9664\u6389\u5185\u5b58\u5206\u914d\uff0c\u5b8c\u5168\u5c06 struct<\/code> \u653e\u5728\u5bc4\u5b58\u5668\u4e2d\uff0c\u4f8b\u5982\u5982\u4e0b\u4ee3\u7801\uff1a<\/p>\n\n\n\n
double Test(int x1, int y1, int x2, int y2)\n{\n    var p1 = new Point(x1, y1);\n    var p2 = new Point(x2, y2);\n    return GetDistance(p1, p2);\n}\n\n[MethodImpl(MethodImplOptions.AggressiveInlining)]\ndouble GetDistance(Point a, Point b)\n{\n    return Math.Sqrt((a.X - b.X) * (a.X - b.X) + (a.Y - b.Y) * (a.Y - b.Y));\n}\n\nstruct Point\n{\n    public Point(int x, int y)\n    {\n        X = x; Y = y;\n    }\n    \n    public int X { get; set; }\n    public int Y { get; set; }\n}\n<\/pre>\n\n\n\n
\u4e0a\u8ff0\u4ee3\u7801 GetDistance<\/code> \u8003\u8651\u662f\u4e2a\u70ed\u70b9\u8def\u5f84\uff0c\u56e0\u6b64\u6211\u52a0 MethodImplOptions.AggressiveInlining<\/code> \u6765\u6307\u5bfc JIT \u6709\u4fdd\u8bc1\u5730\u5185\u8054\u6b64\u51fd\u6570\uff0c\u6700\u540e\u4e3a Test<\/code> \u751f\u6210\u4e86\u5982\u4e0b\u7684\u4ee3\u7801\uff1a<\/p>\n\n\n\n
vzeroupper\t\nsub\tecx, r8d\nmov\teax, ecx\nimul\teax, ecx\nsub\tedx, r9d\nmov\tecx, edx\nimul\tedx, ecx\nadd\teax, edx\nvxorps\txmm0, xmm0, xmm0\nvcvtsi2sd\txmm0, xmm0, eax\nvsqrtsd\txmm0, xmm0, xmm0\nret<\/pre>\n\n\n\n
\u5168\u7a0b\u6ca1\u6709\u4e00\u53e5\u6307\u4ee4\u8bbf\u5b58\uff0c\u975e\u5e38\u7684\u9ad8\u6548\u3002<\/p>\n\n\n\n
\u6211\u4eec\u8fd8\u53ef\u4ee5\u501f\u7528 ref<\/code> \u7684\u5f15\u7528\u8bed\u4e49\u6765\u505a\u539f\u5730\u66f4\u65b0\uff1a<\/p>\n\n\n\n
var vec = new Vector(10);\nvec[2] = 5;\nConsole.WriteLine(vec[2]); \/\/ 5\nref var x = ref vec[3];\nx = 7;\nConsole.WriteLine(vec[3]); \/\/ 7\n\nclass Vector\n{\n    private int[] _array;\n    public Vector(int count) => _array = new int[count];\n    public ref int this[int index] => ref _array[index];\n}\n<\/pre>\n\n\n\n
\u751a\u81f3\u8fd8\u80fd\u642d\u914d\u6307\u9488\u548c\u624b\u52a8\u5206\u914d\u5185\u5b58\u6765\u4f7f\u7528\uff1a<\/p>\n\n\n\n
var vec = new Vector(10);\nvec[2] = 5;\nConsole.WriteLine(vec[2]); \/\/ 5\nref var x = ref vec[3];\nx = 7;\nConsole.WriteLine(vec[3]); \/\/ 7\n\nunsafe class Vector\n{\n    private int* _memory;\n    public Vector(uint count) => _memory = (int*)NativeMemory.Alloc(count, sizeof(int));\n    public ref int this[int index] => ref _memory[index];\n    ~Vector() => NativeMemory.Free(_memory);\n}\n<\/pre>\n\n\n\n
C# \u7684\u6cdb\u578b\u4e0d\u50cf Java \u91c7\u7528\u64e6\u9664\uff0c\u800c\u662f\u771f\u771f\u6b63\u6b63\u4f1a\u5bf9\u6240\u6709\u7684\u7c7b\u578b\u53c2\u6570\u7279\u5316\u4ee3\u7801\uff08\u5c3d\u7ba1\u5bf9\u4e8e\u5f15\u7528\u7c7b\u578b\u4f1a\u5171\u4eab\u5b9e\u73b0\u91c7\u7528\u8fd0\u884c\u65f6\u5206\u53d1\uff09\uff0c\u8fd9\u4e5f\u5c31\u610f\u5473\u7740\u80fd\u6700\u5927\u7a0b\u5ea6\u786e\u4fdd\u6027\u80fd\uff0c\u5e76\u4e14\u5bf9\u5e94\u7684\u7c7b\u578b\u62e5\u6709\u6839\u636e\u7c7b\u578b\u53c2\u6570\u5927\u5c0f\u4e0d\u540c\u800c\u7279\u5316\u7684\u5185\u5b58\u5e03\u5c40\u3002\u8fd8\u662f\u4e0a\u9762\u90a3\u4e2a\u00a0Point<\/code>\u00a0\u7684\u4f8b\u5b50\uff0c\u6211\u4eec\u5c06\u4e0b\u9762\u7684\u6570\u636e\u00a0int<\/code>\u00a0\u6362\u6210\u6cdb\u578b\u53c2\u6570\u00a0T<\/code>\uff0c\u5e76\u505a\u503c\u7c7b\u578b\u6570\u5b57\u7684\u6cdb\u578b\u7ea6\u675f\uff1a<\/p>\n\n\n\n
double Test1(double x1, double y1, double x2, double y2)\n{\n    var p1 = new Point<double>(x1, y1);\n    var p2 = new Point<double>(x2, y2);\n    var result = GetDistanceSquare(p1, p2);\n    return Math.Sqrt(result);\n}\n\ndouble Test2(int x1, int y1, int x2, int y2)\n{\n    var p1 = new Point<int>(x1, y1);\n    var p2 = new Point<int>(x2, y2);\n    var result = GetDistanceSquare(p1, p2);\n    return Math.Sqrt(result);\n}\n\n[MethodImpl(MethodImplOptions.AggressiveInlining)]\nT GetDistanceSquare<T>(Point<T> a, Point<T> b) where T : struct, IBinaryNumber<T>\n{\n    return (a.X - b.X) * (a.X - b.X) + (a.Y - b.Y) * (a.Y - b.Y);\n}\n\nstruct Point<T> where T : struct, IBinaryNumber<T>\n{\n    public Point(T x, T y)\n    {\n        X = x; Y = y;\n    }\n\n    public T X { get; set; }\n    public T Y { get; set; }\n}\n<\/pre>\n\n\n\n
\u65e0\u8bba\u662f Test1<\/code> \u8fd8\u662f Test2<\/code>\uff0c\u751f\u6210\u7684\u4ee3\u7801\u90fd\u975e\u5e38\u4f18\u79c0\uff0c\u4e0d\u4ec5\u4e0d\u5b58\u5728\u4efb\u4f55\u7684\u88c5\u7bb1\u62c6\u7bb1\uff0c\u751a\u81f3\u6ca1\u6709\u4efb\u4f55\u7684\u8bbf\u5b58\u64cd\u4f5c\uff1a<\/p>\n\n\n\n
; Test1\nvzeroupper\t\nvsubsd\txmm0, xmm0, xmm2\nvmovaps\txmm2, xmm0\nvmulsd\txmm0, xmm0, xmm2\nvsubsd\txmm1, xmm1, xmm3\nvmovaps\txmm2, xmm1\nvmulsd\txmm1, xmm1, xmm2\nvaddsd\txmm0, xmm1, xmm0\nvsqrtsd\txmm0, xmm0, xmm0\nret\t\n\n; Test2\nvzeroupper\t\nsub\tecx, r8d\nmov\teax, ecx\nimul\teax, ecx\nsub\tedx, r9d\nmov\tecx, edx\nimul\tedx, ecx\nadd\teax, edx\nvxorps\txmm0, xmm0, xmm0\nvcvtsi2sd\txmm0, xmm0, eax\nvsqrtsd\txmm0, xmm0, xmm0\nret<\/pre>\n\n\n\n
\u63a5\u7740\u8bb2\uff0c\u6211\u4eec\u6709\u65f6\u5019\u4e3a\u4e86\u9ad8\u6027\u80fd\u60f3\u8981\u4e34\u65f6\u6682\u505c GC \u7684\u56de\u6536\uff0c\u53ea\u9700\u8981\u7b80\u5355\u7684\u4e00\u53e5\uff1a<\/p>\n\n\n\n
GC.TryStartNoGCRegion(1024 * 1024 * 128);\n<\/pre>\n\n\n\n
\u5c31\u80fd\u544a\u8bc9 GC \u5982\u679c\u8fd8\u80fd\u5206\u914d 128mb \u5185\u5b58\u90a3\u5c31\u4e0d\u8981\u505a\u56de\u6536\u4e86\uff0c\u7136\u540e\u4e00\u6bb5\u65f6\u95f4\u5185\u4ee5\u540e\u7684\u4ee3\u7801\u6211\u4eec\u5c3d\u7ba1\u5728\u8fd9\u4e2a\u9884\u7b97\u5185\u5206\u914d\u5185\u5b58\uff0c\u4efb\u4f55 GC \u90fd\u4e0d\u4f1a\u53d1\u751f\u3002\u751a\u81f3\u8fd8\u80fd\u963b\u6b62\u5728\u5185\u5b58\u4e0d\u591f\u5206\u914d\u7684\u60c5\u51b5\u4e0b\u8fdb\u884c\u963b\u585e\u5f0f Full GC\uff1a<\/p>\n\n\n\n
GC.TryStartNoGCRegion(1024 * 1024 * 128, true);\n<\/pre>\n\n\n\n
\u4ee3\u7801\u6267\u884c\u5b8c\u4e86\uff0c\u6700\u540e\u7684\u65f6\u5019\u8c03\u7528\u4e00\u53e5\uff1a<\/p>\n\n\n\n
GC.EndNoGCRegion();\n<\/pre>\n\n\n\n
\u5373\u53ef\u6062\u590d GC \u884c\u4e3a\u3002<\/p>\n\n\n\n
\u9664\u6b64\u4e4b\u5916\uff0c\u6211\u4eec\u8fd8\u80fd\u5728\u8fd0\u884c\u65f6\u6307\u5b9a GC \u7684\u6a21\u5f0f\u6765\u6700\u5927\u5316\u6027\u80fd\uff1a<\/p>\n\n\n\n
GCSettings.LatencyMode = GCLatencyMode.Batch;\nGCSettings.LatencyMode = GCLatencyMode.Interactive;\nGCSettings.LatencyMode = GCLatencyMode.LowLatency;\nGCSettings.LatencyMode = GCLatencyMode.NoGCRegion;\nGCSettings.LatencyMode = GCLatencyMode.SustainedLowLatency;\n<\/pre>\n\n\n\n
\u66f4\u8fdb\u4e00\u6b65\uff0c\u6211\u4eec\u751a\u81f3\u53ef\u4ee5\u76f4\u63a5\u5c06\u5806\u5185\u5b58\u4e2d\u7684\u4ee3\u7801\u6267\u884c\uff0c\u5728 .NET \u4e0a\u81ea\u5df1\u9020\u4e00\u4e2a JIT\uff0c\u76f4\u63a5\u4ece\u5185\u5b58\u521b\u5efa\u4e00\u5757\u53ef\u6267\u884c\u7684\u533a\u57df\u7136\u540e\u5f80\u91cc\u9762\u585e\u4e00\u6bb5\u4ee3\u7801\u7528\u6765\u5c06\u4e24\u4e2a32\u4f4d\u6574\u6570\u76f8\u52a0\uff1a<\/p>\n\n\n\n
var kernel32 = NativeLibrary.Load(\"kernel32.dll\");\nvar virtualProtectEx = (delegate* unmanaged[Cdecl, SuppressGCTransition]<nint, void*, nint, int, out int, bool>)NativeLibrary.GetExport(kernel32, \"VirtualProtectEx\");\nvar processHandle = Process.GetCurrentProcess().Handle;\n\nMemory<byte> code = new byte[] {\n    0x8d, 0x04, 0x11, \/\/ lea rax, [rcx+rdx]\n    0xc3              \/\/ ret\n};\n\nusing (var handle = code.Pin())\n{\n    virtualProtectEx(processHandle, handle.Pointer, code.Length, 0x40, out _);\n    var f = (delegate*<int, int, int>)handle.Pointer;\n    Console.WriteLine(f(2, 3)); \/\/ 5\n}\n\nvirtualProtectEx = null;\nNativeLibrary.Free(kernel32);\n<\/pre>\n\n\n\n
\u9664\u6b64\u4e4b\u5916\uff0cC# \u8fd8\u6709\u66f4\u591a\u6570\u4e0d\u6e05\u7684\u5e95\u5c42\u5199\u6cd5\u6765\u548c\u64cd\u4f5c\u7cfb\u7edf\u4ea4\u4e92\uff0c\u751a\u81f3\u5229\u7528 C# \u7684\u7f16\u8bd1\u5668\u53d6\u6d88\u94fe\u63a5\u5230\u81ea\u5df1\u7684\u6807\u51c6\u5e93\uff0c\u76f4\u63a5\u7528\u4ece 0 \u5f00\u59cb\u9020\u57fa\u7840\u7c7b\u578b\u7136\u540e\u901a\u8fc7 NativeAOT \u7f16\u8bd1\u51fa\u5b8c\u5168\u65e0 GC\u3001\u80fd\u591f\u5728\u88f8\u673a\u786c\u4ef6\u4e0a\u6267\u884c\u5f15\u5bfc\u7cfb\u7edf\u7684 EFI \u56fa\u4ef6\u90fd\u662f\u6ca1\u6709\u95ee\u9898\u7684\uff0c\u53c2\u8003\u00a0https:\/\/github.com\/MichalStrehovsky\/zerosharp<\/a><\/p>\n\n\n\n
\u53e6\u5916\u8fd8\u6709 ILGPU \u8ba9\u4f60\u628a C# \u4ee3\u7801\u76f4\u63a5\u8dd1\u5728 GPU \u4e0a\u9762\uff0c\u4ee5\u53ca\u8dd1\u5728\u5d4c\u5165\u5f0f\u8bbe\u5907\u4e0a\u76f4\u63a5\u64cd\u4f5c I2C\u3001PWM\u3001GPIO \u7b49\u7b49\uff0c\u5c31\u4e0d\u518d\u4e3e\u4f8b\u5b50\u4e86\u3002<\/p>\n\n\n\n
\u800c C# \u5df2\u7ecf\u8fdb\u4e86 roadmap \u7684\u540e\u7eed\u66f4\u65b0\u5185\u5bb9\uff1a\u5141\u8bb8\u58f0\u660e\u5f15\u7528\u5b57\u6bb5\u3001\u6dfb\u52a0\u8868\u8fbe\u56fa\u5b9a\u957f\u5ea6\u5185\u5b58\u7684\u7c7b\u578b\u3001\u5141\u8bb8\u4f20\u6570\u7ec4\u65f6\u6d88\u9664\u6570\u7ec4\u5206\u914d\u3001\u5141\u8bb8\u5728\u6808\u4e0a\u5206\u914d\u4efb\u4f55\u5bf9\u8c61\u7b49\u7b49\uff0c\u65e0\u4e00\u4e0d\u662f\u5728\u6539\u8fdb\u8fd9\u4e9b\u5e95\u5c42\u6027\u80fd\u8bbe\u65bd\u3002<\/p>\n\n\n\n
\u4ee5\u4e0a\u5c31\u662f\u6211\u8ba4\u4e3a\u7684 C# \u548c Java \u6700\u5927\u7684\u4e0d\u540c\u3002<\/p>\n\n\n\n
\u5728 C# \u4e2d\u5f53\u4f60\u4e0d\u9700\u8981\u4e0a\u9762\u8fd9\u4e9b\u7684\u4e1c\u897f\u65f6\uff0c\u5b83\u4eec\u4eff\u4f5b\u4ece\u6765\u90fd\u4e0d\u5b58\u5728\uff0c\u5141\u8bb8\u52a8\u6001\u7c7b\u578b\u3001\u4e0d\u65ad\u5438\u6536\u5404\u79cd\u51fd\u6570\u5f0f\u7279\u6027\u3001\u8fd8\u6709\u5404\u79cd\u8bed\u6cd5\u7cd6\u52a0\u6301\uff0c\u7b80\u6d01\u5ea6\u548c\u7075\u6d3b\u5ea6\u751a\u81f3\u4e0d\u8f93 Python\uff0c\u975e\u5e38\u6109\u5feb\u548c\u7b80\u5355\u5730\u5c31\u80fd\u7f16\u5199\u5404\u79cd\u4ee3\u7801\uff1b\u800c\u4e00\u65e6\u4f60\u9700\u8981\uff0c\u4f60\u53ef\u4ee5\u62e5\u6709\u4ece\u4e0a\u5c42\u5230\u5e95\u5c42\u7684\u51e0\u4e4e\u5b8c\u5168\u7684\u63a7\u5236\u80fd\u529b\uff0c\u800c\u8fd9\u4e9b\u80fd\u529b\u5c06\u80fd\u8ba9\u4f60\u6709\u9700\u8981\u65f6\u65e0\u9700\u601d\u8003\u5404\u79cd\u5947\u602a\u7684 workaround \u5c31\u80fd\u76f4\u63a5\u69a8\u5e72\u673a\u5668\uff0c\u8fbe\u5230 C\u3001C++ \u7684\u6027\u80fd\uff0c\u751a\u81f3\u56e0\u4e3a\u6709\u8fd0\u884c\u65f6 PGO \u800c\u8d85\u51fa C\u3001C++ \u7684\u6027\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u539f\u6587\uff1aJava \u548c C# \u6700\u5927\u7684\u4e0d\u540c\u662f\u4ec0\u4e48\uff1f – \u77e5\u4e4e…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[],"class_list":["post-107","post","type-post","status-publish","format-standard","hentry","category-c"],"_links":{"self":[{"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/posts\/107","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/comments?post=107"}],"version-history":[{"count":1,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/posts\/107\/revisions"}],"predecessor-version":[{"id":108,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/posts\/107\/revisions\/108"}],"wp:attachment":[{"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/media?parent=107"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/categories?post=107"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/xiuxiejiang.com\/index.php\/wp-json\/wp\/v2\/tags?post=107"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}